Parts for your 2012 Subaru Exiga-Throttle position sensors

2012 Subaru Exiga throttle position sensors (TPS) — what they do, and how to look after them

Based on Subaru factory service information for the YA-chassis Exiga (Engine Control System — Electronic Throttle Control) and Subaru FAST parts catalog listings for MY2012, the 2012 Subaru Exiga does use throttle position sensors. They’re built into the electronic throttle body along with the throttle actuator motor, and the accelerator pedal uses a separate dual-position pedal sensor. Diagnostic references in Subaru manuals also list TPS-related DTCs (P0121–P0123, P2135), confirming its role on this model.

On a 2012 Exiga, the throttle position sensors measure the actual angle of the throttle plate and feed that info to the ECU. Paired with the accelerator pedal sensor, the ECU can precisely control the electronic throttle for smooth take-off, stable idle, cruise control operation, traction stability, and the right fuelling and ignition timing. Subaru uses dual TPS tracks inside the throttle body for redundancy, so the ECU can compare signals and spot anything dodgy before it affects driveability.

Servicing-wise, there’s no separate bolt-on TPS on this Exiga — the sensors are part of the throttle body assembly. If a sensor fails or goes out of range, the usual fix is replacing the throttle body as a unit. Before replacing parts, it’s smart to scan live data and check wiring under the bonnet for corrosion or loose pins at the throttle body connector and at the pedal.

• Common symptoms of TPS faults: hesitant throttle, limp-home mode, erratic idle, poor fuel economy, cruise dropping out, and warning lights with codes like P0121–P0123 or P2135.
• Cleaning tips: you can gently clean light carbon from the throttle bore and plate using throttle-body-safe cleaner. Don’t force the butterfly by hand and avoid flooding the shaft seals.
• After battery disconnection, cleaning, or throttle body replacement, perform an idle/throttle relearn. This can be done with a scan tool or by following the Subaru drive cycle and warm-up procedure from the service manual.
• When replacing the throttle body, fit a new gasket, torque to spec, and clear codes. Confirm both TPS tracks and the pedal signals track smoothly and agree in live data.

These points align with Subaru’s factory service manual guidance and the parts catalog description of the “Throttle Body Assy. (with motor & sensor)” for the 2012 Exiga.

Does the 2012 Subaru Exiga have a separate TPS, or is it built into the throttle body?
The TPS is integrated into the electronic throttle body on this model, with dual sensor tracks for redundancy. There isn’t a separate, serviceable TPS like on older cable-throttle Subarus. If the sensor fails, the throttle body assembly is typically replaced after wiring checks.

What are the tell-tale signs the TPS is playing up on a 2012 Exiga?
Drivers may notice sluggish response, intermittent limp mode, unstable idle, cruise control cutting out, or the check engine light. Scan tools often show codes such as P0121–P0123 or P2135, and live data will reveal jumpy or mismatched throttle angle readings.

Can the TPS be cleaned or reset, or does it always need replacing?
The sensor itself is sealed, so it isn’t a clean-and-reuse item. Lightly cleaning carbon from the throttle bore can help idle quality, but if TPS correlation or range faults persist, replacement of the throttle body is the usual remedy. Always carry out an idle/throttle relearn after work is completed.